copper
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What is copper?
Copper (Cu) is a reddish metal with very high ductility and is an excellent conductor of heat and electricity. It is a chemical element in Group 11 (Ib) of the periodic table.
Copper is found as a free metal in nature. It also occurs in minerals like chalcocite, chalcopyrite, and bornite. Copper is produced through smelting or leaching, often followed by electrodeposition.
Most copper is used in the electrical industry. It is also used to create alloys like brass (copper and zinc) and bronze (copper and tin).
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What are some common uses of copper?
Copper is widely utilized across various industries due to its properties. The electrical industry uses the major portion of copper produced globally. It is used in electrical machinery and in the form of copper wires and cables, given its high electrical conductivity.
Copper is also alloyed with other metals like zinc, tin, and nickel to create brasses, bronzes, and nickel silvers. Copper is found in tools, weapons, cooking vessels, household utensils, mirrors, and ornaments. Additionally, copper is used in coinage metals.
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What does copper look like, and what are its physical properties?
Copper (Cu) is a reddish metal with extremely high ductility and is an excellent conductor of heat and electricity. It is found in its free metallic state in nature.
Physical properties of copper:
* Atomic number: 29
* Atomic weight: 63.546
* Melting point: 1,083 °C (1,981 °F)
* Boiling point: 2,567 °C (4,653 °F)
* Density: 8.96 at 20 °C (68 °F)
* Valence: 1, 2
* Electron configuration: 2-8-18-1 or (Ar)3d104s14 Britannica SourcesCreated from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles. -
Why is copper a good conductor of electricity and heat?
Copper stands out as an exceptional conductor of both electricity and heat due to its metallic bonds, characterized by mobile valence electrons that move freely within the crystal lattices. These non-localized electrons facilitate the easy transfer of electrical charge and thermal energy throughout the metal.
The ability of a metal to conduct electricity depends not only on the number of free electrons but also on their mobility, which refers to how easily electrons move through the solid when an electric field is applied. Even small amounts of impurities can interfere with electron movement, which is why pure copper is a better conductor than copper alloys.
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Where is copper found and how is it obtained from nature?
Copper is found in both its native form and in various minerals such as chalcocite, chalcopyrite, bornite, cuprite, malachite, and azurite. Major copper-producing countries include Chile, Peru, China, and the United States.
Copper extraction from ore involves three main steps: mineral processing, smelting or leaching, and refining. Mineral processing liberates copper minerals and removes waste. Smelting or leaching removes impurities like iron and sulfur. Finally, refining removes the remaining impurities to produce a copper product with 99.99 percent purity.
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How do humans recycle and reuse copper, and why is this important?
Humans recycle and reuse copper through internal and external recycling operations. Internal recycling involves reusing waste from manufacturing processes, such as remelting and recasting copper tube ends and trimmings. External recycling reclaims copper from worn-out or obsolete products.
The importance of copper recycling lies in its economic and environmental benefits. Recycling reduces the need for raw materials from increasingly scarce natural resources and lowers the amount of solid waste in landfills. It also helps to reduce air, water, and land pollution from waste disposal.
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News •
copper (Cu), chemical element, a reddish, extremely ductile metal of Group 11 (Ib) of the periodic table that is an unusually good conductor of electricity and heat. Copper is found in the free metallic state in nature. This native copper was first used (c. 8000 bce) as a substitute for stone by Neolithic (New Stone Age) humans. Metallurgy dawned in Mesopotamia as copper was cast to shape in molds (c. 4000 bce), was reduced to metal from ores with fire and charcoal, and was intentionally alloyed with tin as bronze (c. 3500 bce). The Roman supply of copper came almost entirely from Cyprus. It was known as aes Cyprium, “metal of Cyprus,” shortened to cyprium and later corrupted to cuprum. See also bronze.
| atomic number | 29 |
|---|---|
| atomic weight | 63.546 |
| melting point | 1,083 °C (1,981 °F) |
| boiling point | 2,567 °C (4,653 °F) |
| density | 8.96 at 20 °C (68 °F) |
| valence | 1, 2 |
| electron configuration | 2-8-18-1 or (Ar)3d104s1 |
Occurrence, uses, and properties
Native copper is found at many locations as a primary mineral in basaltic lavas and also as reduced from copper compounds, such as sulfides, arsenides, chlorides, and carbonates. (For mineralogical properties of copper, see the table of native elements.) Copper occurs combined in many minerals, such as chalcocite, chalcopyrite, bornite, cuprite, malachite, and azurite. It is present in the ashes of seaweeds, in many sea corals, in the human liver, and in many mollusks and arthropods. Copper plays the same role of oxygen transport in the hemocyanin of blue-blooded mollusks and crustaceans as iron does in the hemoglobin of red-blooded animals. The copper present in humans as a trace element helps catalyze hemoglobin formation. A porphyry copper deposit in the Andes Mountains of Chile is the greatest known deposit of the mineral. By the early 21st century Chile had become the world’s leading producer of copper. Other major producers include Peru, China, and the United States.
Copper is commercially produced mainly by smelting or leaching, usually followed by electrodeposition from sulfate solutions. For a detailed treatment of the production of copper, see copper processing. The major portion of copper produced in the world is used by the electrical industries; most of the remainder is combined with other metals to form alloys. (It is also technologically important as an electroplated coating.) Important series of alloys in which copper is the chief constituent are brasses (copper and zinc), bronzes (copper and tin), and nickel silvers (copper, zinc, and nickel, no silver). There are many useful alloys of copper and nickel, including Monel; the two metals are completely miscible. Copper also forms an important series of alloys with aluminum, called aluminum bronzes. Beryllium copper (2 percent Be) is an unusual copper alloy in that it can be hardened by heat treatment. Copper is a part of many coinage metals. Long after the Bronze Age passed into the Iron Age, copper remained the metal second in use and importance to iron. By the 1960s, however, cheaper and much more plentiful aluminum had moved into second place in world production.
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| country | mine production 2016 (metric tons)* | % of world mine production | demonstrated reserves 2016 (metric tons)* | % of world demonstrated reserves |
|---|---|---|---|---|
| *Estimated. | ||||
| **Because of rounding, details do not add up to total given. | ||||
| Source: U.S. Department of the Interior, Mineral Commodity Summaries 2017. | ||||
| Chile | 5,500,000 | 28.4 | 210,000,000 | 29.2 |
| Peru | 2,300,000 | 11.9 | 81,000,000 | 11.3 |
| China | 1,740,000 | 9.0 | 28,000,000 | 3.9 |
| United States | 1,410,000 | 7.3 | 35,000,000 | 4.9 |
| Australia | 970,000 | 5.0 | 89,000,000 | 12.4 |
| Congo (Kinshasa) | 910,000 | 4.7 | 20,000,000 | 2.8 |
| Zambia | 740,000 | 3.8 | 20,000,000 | 7.4 |
| Canada | 720,000 | 3.7 | 11,000,000 | 1.5 |
| Russia | 710,000 | 3.7 | 30,000,000 | 4.2 |
| Mexico | 620,000 | 3.2 | 46,000,000 | 6.4 |
| other countries | 3,800,000 | 19.6 | 150,000,000 | 20.8 |
| world total | 19,400,000** | 100** | 720,000,000 | 100** |
Copper is one of the most ductile metals, not especially strong or hard. Strength and hardness are appreciably increased by cold-working because of the formation of elongated crystals of the same face-centred cubic structure that is present in the softer annealed copper. Common gases, such as oxygen, nitrogen, carbon dioxide, and sulfur dioxide are soluble in molten copper and greatly affect the mechanical and electrical properties of the solidified metal. The pure metal is second only to silver in thermal and electrical conductivity. Natural copper is a mixture of two stable isotopes: copper-63 (69.15 percent) and copper-65 (30.85 percent).
Because copper lies below hydrogen in the electromotive series, it is not soluble in acids with the evolution of hydrogen, though it will react with oxidizing acids, such as nitric and hot, concentrated sulfuric acid. Copper resists the action of the atmosphere and seawater. Exposure for long periods to air, however, results in the formation of a thin green protective coating (patina) that is a mixture of hydroxocarbonate, hydroxosulfate, and small amounts of other compounds. Copper is a moderately noble metal, being unaffected by nonoxidizing or noncomplexing dilute acids in the absence of air. It will, however, dissolve readily in nitric acid and in sulfuric acid in the presence of oxygen. It is also soluble in aqueous ammonia or potassium cyanide in the presence of oxygen because of the formation of very stable cyano complexes upon dissolution. The metal will react at red heat with oxygen to give cupric oxide, CuO, and, at higher temperatures, cuprous oxide, Cu2O. It reacts on heating with sulfur to give cuprous sulfide, Cu2S.
